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arXiv · 2003.06607

Universal finite-time thermodynamics of many-body quantum machines from Kibble-Zurek scaling

Revathy B. S.·Victor Mukherjee·Uma Divakaran·Adolfo del Campo
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Abstract

We demonstrate the existence of universal features in the finite-time thermodynamics of quantum machines by considering a many-body quantum Otto cycle in which the working medium is driven across quantum critical points during the unitary strokes. Specifically, we consider a quantum engine powered by dissipative energizing and relaxing baths. We show that under very generic conditions, the output work is governed by the Kibble-Zurek mechanism, i.e., it exhibits a universal power-law scaling with the driving speed through the critical points. We also optimize the finite-time thermodynamics as a function of the driving speed. The maximum power and the corresponding efficiency take a universal form, and are reached for an optimal speed that is governed by the critical exponents. We exemplify our results by considering a transverse-field Ising spin chain as the working medium. For this model, we also show how the efficiency and power vary as the engine becomes critical.

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Revathy B. S., Victor Mukherjee, Uma Divakaran, Adolfo del Campo. 2020-03-14. Universal finite-time thermodynamics of many-body quantum machines from Kibble-Zurek scaling. https://doi.org/10.1103/physrevresearch.2.043247

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